FAMILY DERODONTIDAE (Tooth-necked fungus beetles) D.E. Bright The family Derodontidae includes four genera and 19 species of small beetles that occur in the temperate parts of both the Northern and Southern Hemispheres. They are rarely encountered in the field and are uncommon in collections. Three genera and eight species are found in Canada and Alaska. With the exception of Laricobius species, members of this family feed as both larvae and adults on various kinds of fungi or the products of fungal metabolism. Peltastica appear to be restricted to fermenting sap flows or to areas under bark where bacterial or fungal fermentation is taking place. Derodontus species feed on the fruiting bodies of a wide range of higher Basidiomycetes. Fresh fruiting bodies are preferred by the beetles, although they have been recorded from rotting mushrooms, "slimy fungus" and "watery fungus". The feeding habits of Laricobius erichsonii have been well documented by Franz (1958). Adults and larvae feed on the pine and spruce aphids in the family Adelgidae. The preferred host of L. erichsonii is the balsam woolly aphid and the species was introduced into eastern Canada in the 1950's for the control of this pest. The other species of Laricobius also feed on other species of Adelgidae. Information on adult and larval morphology, feeding behavior, life cycle, evolution and keys and diagnosis of all genera and species may be found by consulting Lawrence and Hlavac (1979). AK (2); BC (5); AB (1); ON (2); PQ (1); NB (2); NS (3); NF (1) Subfamily PELTASTICINAE Genus PELTASTICA Mannerheim P. tuberculata Mannerheim AK - - BC - - - - - - - - - - Subfamily DERODONTINAE Genus LARICOBIUS Rosenhauer L. erichsonii Rosenhauer+ - - - BC - - - - - NB NS - - NF L. laticollis Fall - - - BC AB - - - - - - - - - L. nigrinus Fender - - - BC - - - - - - - - - - L. rubidus LeConte - - - - - - - ON PQ NB - - - - Genus DERODONTUS LeConte D. esotericus Lawrence - - - - - - - ON - - NS - - - D. maculatus (Melsheimer) - - - - - - - - - - NS - - - D. trisignatus (Mannerheim) AK - - BC - - - - - - - - - - .